Cardiac Strain
Having defined the endo- and epicardial borders at all
time points, and set up the segments,
you can perform cardiac strain analysis. Strain analysis uses an image
registration technique to assess the movement of tissue across time-points, and
is applicable to any cardiac cine sequence, whether tagged or not.
Select the "Strain" tab in the Cardiac Segment toolkit:
![Cardiac Strain analysis](cardiac_strain.gif)
Then press the
button. This will start the registration process, and
after a few minutes, you will see pop-up graphs
showing the radial and circumferential strain in each segment through the
cardiac cycle, and a dialog asking
whether you want to save the results of the analysis to either a text or a PDF report:
![Dialog for the Cardiac Strain analysis results](cardiac_strain_report.gif)
If you write a report, it will contain tables of radial and circumferential
strain for each physical image slice. Any division into endo- and epicardium is
ignored.
In addition, there are bulls-eye plots and tables showing the minimum (maximum
negative) circumferential strain and maximum radial strain, as shown in the
examples below for a 6-slice image, where 4 of the slices has the endo- and
epicardial borders defined, and the last 2 apical slices did not.
Strain analysis also outputs cine images showing the radial and circumferential
strain through the cardiac cycle. The images will have the same name as the
input image, but with the suffixes _eRR
for the radial strain
image, and _eCC
for the circumferential strain. The examples
shown below were calculated from a regular (non-tagged) cine pulse sequence.
![](eRR.gif) | ![](eCC.gif) |
Radial strain image | Circumferential strain image |